Door handles

I am nearly up to four operational door handles on my 4000, having visited
the local junk yards. I had no problems with the rear handles, but
the front one, which also locks/unlocks the door with the
key, is a hard one to put on. Has anyone succeeded assembling it
without taking off the inner panel? If you have done that, then
you know what I am talking about! I would appreciate some pointers
on it.
Thanks, Peter
orban@nrcamt.nrc.ca